James h



(No Model.)

J. H.,KELLY 8v 0'. H. BROAD' TUBE.

No. 369,012. Patented Aug. so, 1387.

UNITED STATES PATENT OE rcE.

JAMES H. KELLY AND CHARLES H. BROAD, OF ROCHESTER, NEW YORK; SAID BROADASSIGNOR TO SAID KELLY.

TUBE.

SPECIFICATION forming part of Letters Patent No. 369,012, dated August30, 1887.

' Application filed February 23,1887. Serial No. 228,611. (No model.)

.To aZZ whom, it may concern:

Be it known that we, JAMES H. KELLY and CHARLES H. BROAD, both citizensof the United States, residing at Rochester, in the county of Monroe andState of New York, have invented a certain new and useful Improvement inBent Tubes and Pipes; and we do hereby declare that the following is afull, clear, and exact description of the same, reference being bad tothe drawings accompanying this application.

Our improvement relates to bent tubes and pipes produced from a singlepiece and made by bending the tube around a form.

Heretofore it has been the practice to fill the tube with sand or othermaterial, then hold the ends firmly against clamps, and then produce thebending action, the-filling preventing the collapse of the tube while itis being bent; but in such case the strain is great and the tube hasnecessarily to upset or corrugate on the inside of the bend, which isobjectionable to the sight, besides which the filling will yield, andthe consequence is, the tube is somewhat flattened at the bend and doesnot preserve a true circle in cross-section. Tubes are also bent by handin a similar manner.

In contradistinction to such tubes our invention consists of a tubeinwhich the bend is made without necessarily upsetting or corrugating thesides, presenting a smooth surface,and the tube not being flattened, butpresenting practically a circle in cross-section at any point, and beingof the same diameter its whole extent.

In the drawings, Figure 1 is an elevation of a piece of the bent pipe,the bend being shown in section. Fig. 2 is a cross-section of the samein line x 00 of Fig. 1. Fig. 3 is a longitudinal vertical section of themachine by which the bending is done, the same being shown of reducedsize.

,J shows a piece of tube provided with a bend, J, said bend being madeof any desired curve and in any part of the tube. In crosssection thetube is practically a circle at any point in its length, as shown inFig. 2. The tube is also smooth on all sides, and is not necessarilycrimped or corrugated in the bend,

as in ordinary tubes bent by machinery over a form.

Fig. 3 shows one form of machine by which the tube is bent. A indicatesa bed-plate, and A a circular forming-head, both provided with a halfcircular groove, a, in which the tube is laid.

B is a clamp, also provided with a half-circular groove on its underside, said clamp .being forced down by suitable means to fasten the tubein place on the bed.

0 is a yoke resting on the journals of the forming-head A and capable ofbeing turned in a circle, as indicated by the arrow, Fig. 3.

D is a die, pivoted at g in a fork ofithe yoke, and provided at itslower end with a halfcircular groove that fits the tube. The yoke anddie have levers or handles f h and swing together around theforming-head. G is a stirrup pivoted or attached to the sides of theyoke and turning with it.

E is a rod resting in the stirrup and inserted in the tube. to bebentand extending inward to the right position between the forming-head Aand die D. I

When the yoke and die are swung around the forminghead, the rod E willalso turn around the forming-head, and will have a drawing movementcoincident with the bending of the tube, and the end or head resting atthe point where the bending takes place it forms a core and will leavethe tube practically circular in crosssection its whole length. The headof the rod E, in drawing around the forming'head, bears against bothsides or faces of the inside of the tube and keeps said sides closepressed against the grooved bed. in which the tube lies, so that itcannot wrinkle or crimp, and therefore it will be bent with perfectlysmooth sides. Nevertheless, by changing the position of the rod E, thetube can be crimped or ribbed at the bend when desired. Tubes bent inthis manner differ materially from tubes bent in the ordinary way bybeing round in cross-section and having a perfectly smooth exterior andbeing of the same diameter their whole extent, and therefore not onlypresent a better appearance, but are stronger and more serviceable, asany flattening of the tube renders it weak and liable to collapse.

Having described our invention, what we claim as new, and desire tosecure by Letters Patent, is-

1. As an improved article of manufacture, a bent tube or pipe made froma sheet-metal blank of uniform width and thickness, having a singlelongitudinal scam, the bend being at any desired point in the length,circular in cross-section, smooth on the outside, and of the samediameter its whole length, substantially as shown and described.

2. As an improved article of manufacture, a bent tube or pipe made froma sheet-metal blank of uniform width and thickness, having a singlelongitudinal seam, the bend being at any desired'point in the length,circular in cross-section, smooth on the outside, and of the samediameter its whole length, and hav- 2o ing both ends extended in astraight line beyond the curve, substantially as shown and described.

In witness whereof we have hereunto signed our names in the presence oftwo subscribing 25 witnesses.

JAMES H. KELLY. CHARLES H. BROAD.

Witnesses:

PARKHURST W. J ERAULD, JACOB A. RITZ.

